Res Judicata and the protection of registered designs in the EU and UK post-Brexit (Praesidiad v Zaun)
IP analysis: The Court of Appeal upheld a High Court decision striking out Zaun Ltd’s (Zaun) counterclaim challenging the validity of a registered EU Design (REUD) and its UK re-registered design (UKRRD) equivalent. Praesidiad Holding BVBA (Praesidiad), previously known as Betafence, the design rights holder, had already successfully defended the design’s validity through the European Union Intellectual Property Office (EUIPO) and EU courts. The Court of Appeal ruled that Zaun’s renewed UK challenge was barred by res judicata (the legal doctrine preventing re-litigation of claims or issues that have already been resolved by a competent court) and constituted an abuse of process, despite the UK’s departure from the EU. The decision reinforces that EUIPO judgments, particularly where upheld by the EU General Court, may remain binding in UK proceedings involving post-Brexit re-registered rights. For rights holders, this affirms the continued value and enforceability of EU-originated IP rights in the UK. For defendants, it highlights the importance of raising and resolving validity issues in the appropriate forum, as opportunities to re-litigate in the UK may be limited once EU decisions have reached finality. Written by Amanda McDowall, partner, and Saher Amin, trainee solicitor, at Lee & Thompson LLP.